Mis-marked 70mm Medusa?
 

I bought a 70mm Medusa. 36-70-1600, and my original plan was to run it in my truugy. After a couple runs I wasn't impressed with the power so I put my Neu in the truggy and the Medusa in my E-Revo for bashing. Power seemed decent but temps where pretty high, 165-170* (also got real warm in truggy) and it was running really fast. I now have my Revo geared as low as I can with what I have, 68/20 gearing - 1600kv - 5s - Masher tires, calculator puts it at about 29MPH but the thing still hauls!!! Now that same setup but 2000kv puts me around 36, much closer to what it's doing! I also plugged the numbers in for the truggy and that's what makes me think that this motor is marked wrong. If I had it overgeared in the truggy performance would suffer and have higher temps right?

Anybody think this is possible???
Anyway to check?


E-Revo/5s/1600kv

Differential Ratio: 2.8461538461538462
Transmission Ratio: 1.8333333333333332
Other Ratio: 1
Spur Tooth Count: 68
Pinion Tooth Count: 20
Total Voltage: 18.5
Motor KV: 1600
Tire Diameter (inches): 5.8
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.007
Spur/Pinion Ratio: 3.4 : 1
Total Ratio: 17.74103 : 1
Tire Circumference (inches): 18.22 inches (462.82 mm)
Total Motor Speed: 29600 RPM
Vehicle Speed: 28.79 mph (46.25 km/h)
Effective KV Value: 1600

E-Revo/5s/2000kv
Differential Ratio: 2.8461538461538462
Transmission Ratio: 1.8333333333333332
Other Ratio: 1
Spur Tooth Count: 68
Pinion Tooth Count: 20
Total Voltage: 18.5
Motor KV: 2000
Tire Diameter (inches): 5.8
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.005
Spur/Pinion Ratio: 3.4 : 1
Total Ratio: 17.74103 : 1
Tire Circumference (inches): 18.22 inches (462.82 mm)
Total Motor Speed: 37000 RPM
Vehicle Speed: 35.99 mph (57.81 km/h)
Effective KV Value: 2000

RC8T/5s/1600kv
Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 54
Pinion Tooth Count: 17
Total Voltage: 18.5
Motor KV: 1600
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.007
Spur/Pinion Ratio: 3.18 : 1
Total Ratio: 13.65882 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Total Motor Speed: 29600 RPM
Vehicle Speed: 36.43 mph (58.51 km/h)
Effective KV Value: 1600

RC8T/5s/2000kv

Differential Ratio: 4.3
Transmission Ratio: 1
Other Ratio: 1
Spur Tooth Count: 54
Pinion Tooth Count: 17
Total Voltage: 18.5
Motor KV: 2000
Tire Diameter (inches): 5.65
Tire Ballooning (inches): 0
Motor Current Draw: 0
Motor coil Ω: 0.005
Spur/Pinion Ratio: 3.18 : 1
Total Ratio: 13.65882 : 1
Tire Circumference (inches): 17.75 inches (450.85 mm)
Total Motor Speed: 37000 RPM
Vehicle Speed: 45.53 mph (73.14 km/h)
Effective KV Value: 2000

I suppose it is possible. Only way to tell really would be to measure the rpm (via telemetry or something) at a set voltage.

I had a mismarkes Neu 1512 a while back. I ordered a 2.5d, the box was labeled 2.5d, but got a 2d. Like you, it was quite a bit faster than I expected. So, it does happen.

gps it? eyeballing speed leaves much room for error. or make a speed trap.

My 36-70-1600 is pretty freakn fast in my truggy on 5s too. I was actually thinking it may have been mismarked too.

+1. I can eyeball speeds of land vehicles pretty well but to be the most accurate you'll need to GPS it, radar it, or at very least use a speed trap (mark off 100 feet or so, see how long it takes to cross that distance then do the math). You'll need to be rather close on your estimates of tire ballooning, that could easily throw you off.

I might not have a radar eye but the 29mph it is geared for is about the speed of a stock e-revo. It is going a hell of a lot faster than that! It is about the same as when I had it geared for 38 with my neu. I don't own a gps and a speed trap has to many variables. Time to find a friendly cop again! But I'm gonna go with it being a 2000kv motor till I figure otherwise

My BPP truggy is geared for 34MPH (Actually close to 35MPH), but I got it on radar at 46MPH. Now I added some tire ballooning (Which the truggy had plenty of) and the speed was exactly what I saw on radar.